In the film version, Laura (played by Dafne Keen) will be seen as a child who enters Wolverine’s life when he’s trying to lay low. The film’s near-future setting finds a grizzled, weary Logan (Hugh Jackman) scratching out an existence in a desert town near the Mexican border. Caring for an ailing, nonagenarian Charles Xavier (Patrick Stewart), he’s trying to avoid trouble while working as a limo driver. But trouble never seems very far from his life, and he’s asked to get Laura to safety when dark forces close in on her location. He’s not sure about this quiet, haunted young woman, but realises she has more in common with him than he first thought… particularly when her life is in danger.
Who is X-23?
When a top-secret program attempted to recreate the original Weapon X experiment that involved the feral mutant Wolverine, they failed to secure a test subject that could survive the bonding of the virtually unbreakable metal Adamantium to their skeleton. Seeking to take the project in a new direction, the project’s director, Doctor Martin Sutter, recruited renowned mutant geneticist Doctor Sarah Kinney and tasked her with creating a clone. Using the only available genetic sample from Weapon X, which was damaged, they were unable to salvage the Y chromosome after 22 attempts. Kinney then proposed they create a female clone, and though her request was initially denied, she still went ahead and produced a viable female subject, prompting Sutter to reconsider. Despite resistance from his protégé Doctor Zander Rice, whom he had raised after Rice’s father was killed by a bestial Wolverine at the original Weapon X Project, Sutter allowed Kinney to proceed. As revenge for her insubordination, Rice forced Kinney to act as the surrogate mother for the clone, and she gave birth to “X-23.”
More info in Marvel website